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High Volume vs Standard Volume Oil Pump
#1337680
11/19/12 11:46 AM
11/19/12 11:46 AM
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Joined: Jun 2006
Posts: 5,162
CT
GTX MATT
OP
master
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OP
master
Joined: Jun 2006
Posts: 5,162
CT
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Alright guys, so I initially bought a high volume pump because I was planning to run an 8 quart pan. I decided I didn't want to deal with ground clearance issues, and bought a repop 71 Hemi 6 quart pan. I bought a standard volume pump at the same time, figuring I don't want to risk running the pan dry and I'd use the HV pump on something else. Now I'm starting to rethink. What thinks Moparts?
This is a street car with .0027 clearance on the mains and .0025 on the rods. It will see some strip time and is driven hard on the street.
Now I need to pin those needles, got to feel that heat
Hear my motor screamin while I'm tearin up the street
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Re: High Volume vs Standard Volume Oil Pump
[Re: jamesc]
#1337683
11/19/12 01:55 PM
11/19/12 01:55 PM
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Joined: Jun 2006
Posts: 5,162
CT
GTX MATT
OP
master
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OP
master
Joined: Jun 2006
Posts: 5,162
CT
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Also want to throw in this engine has aluminum heads
Now I need to pin those needles, got to feel that heat
Hear my motor screamin while I'm tearin up the street
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Re: High Volume vs Standard Volume Oil Pump
[Re: jamesc]
#1337684
11/19/12 03:03 PM
11/19/12 03:03 PM
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Joined: Aug 2003
Posts: 43,190
Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,190
Bend,OR USA
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Quote:
personally i think the HV pump sucking the pan dry is a wives tale. if both the HV and standard pump carry the same oil pressure throughout the operating range then the exact same amount of oil is being pumped through the engine the only difference is the HV pump is internally recirculating more oil.
the best pump for the application is the smallest pump that will deliver the desired oil pressure under the expected operating conditions. anything else is a waste of HP and unnecessary load on the drive system
 OP, my 518 pump gas stroker has more bearing clearances than yours as well as oiling the rockers full time, I use the same oil pan  I use 5W20WT Valvoline non synthetic, I have to keep the oil level above the add mark at the drag strip, if I don't the oil pressure will drop off when I let off. I cross the finish line between 6500 and 7000 RPM depending on which rear tires are on the car, it runs 134.+ MPH  I did cut the bypass spring down so I have right at 65 lbs of pressure at 6500 RPM with hot oil on the engine dyno, I think it was 1 1/2 coils 
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: High Volume vs Standard Volume Oil Pump
[Re: dartman366]
#1337686
11/19/12 03:57 PM
11/19/12 03:57 PM
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Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
Streetwize
master
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master
Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
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I run a blueprinted and hand ported stock volume pump on any of my big blocks that turn up to ~7200 rpm. You'd be suprised what they'll keep up with by just opening up the inlet to 1/2" and chamfering that severe 90 degree turn in the pump head itself Both the high-volume and standard pumps seem to have the same inlet/outlet "head" casting; I for one never saw the point/value of opening up the block pick-up to 1/2" and leaving the restrictive 3/8" id head on the pump if you make it easy to supply the oil to the pump and provide it relatively unrestricted to the mains, you make it a lot easier for the system to do its job. The interesting thing about oiling systems is since you have a series of controlled orifice "bleeds" ; so as you bleed pass each journal you have proportionally less oil pressure available for the next one in the path. Therefore the 'easiest' (and arguably most effective) ways to help the system "circuit" is to reduce as many upstream bottlenecks as you can. The pump head is the first place I go toward improving the system.
Last edited by Streetwize; 11/19/12 03:58 PM.
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Re: High Volume vs Standard Volume Oil Pump
[Re: Streetwize]
#1337688
11/19/12 09:16 PM
11/19/12 09:16 PM
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Joined: Nov 2009
Posts: 2,275
Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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Quote:
I run a blueprinted and hand ported stock volume pump on any of my big blocks that turn up to ~7200 rpm. You'd be suprised what they'll keep up with by just opening up the inlet to 1/2" and chamfering that severe 90 degree turn in the pump head itself
Both the high-volume and standard pumps seem to have the same inlet/outlet "head" casting; I for one never saw the point/value of opening up the block pick-up to 1/2" and leaving the restrictive 3/8" id head on the pump
if you make it easy to supply the oil to the pump and provide it relatively unrestricted to the mains, you make it a lot easier for the system to do its job.
The interesting thing about oiling systems is since you have a series of controlled orifice "bleeds" ; so as you bleed pass each journal you have proportionally less oil pressure available for the next one in the path. Therefore the 'easiest' (and arguably most effective) ways to help the system "circuit" is to reduce as many upstream bottlenecks as you can. The pump head is the first place I go toward improving the system.
with 'Wise. I would definitely enlarge the suction side (pump head) of the block to 1/2" (Hemi diameter) and chamfer the 90 degree bend to the pump mount. As far as the pump is concerned with, hi-volume is what I'd go with. 6 Quart pan is fine, but and 7-8 quart "kickout-style" pan is a little better. More capacity, ground clearance is good but... it may or may not work for you, depending on your steering linkage clearances and chassis. Check on it. Oil lubricates and HELPS cool also, the more oil capacity, the better. 
"Stupidity is Ignorance on Steroids"
"Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: High Volume vs Standard Volume Oil Pump
[Re: GTX MATT]
#1337691
11/20/12 08:48 AM
11/20/12 08:48 AM
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Joined: Feb 2005
Posts: 4,314
Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,314
Prospect, PA
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There are so many other clearances that matter that we don't talk about so it is hard to say.
I have .0028/.0022, full groove mains, full time unrestricted oiling to the valve gear, hand massaged std. rotor pump, and 5-30 full synthetic oil. Hot, in gear (700 rpm) is about 18-20 psi, neutral (850 rpm) 20-23 psi. It climbs to 50+ with the slightest amount of throttle.
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Re: High Volume vs Standard Volume Oil Pump
[Re: jamesc]
#1337692
11/20/12 10:27 AM
11/20/12 10:27 AM
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Joined: May 2004
Posts: 12,388
Taxes & Virus's R-US, NY
Dragula
I Live Here
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I Live Here
Joined: May 2004
Posts: 12,388
Taxes & Virus's R-US, NY
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Quote:
personally i think the HV pump sucking the pan dry is a wives tale.
I will send you my burnt rod.....Was running 9.5 quarts, and starved one rod.
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Re: High Volume vs Standard Volume Oil Pump
[Re: Dragula]
#1337696
11/20/12 11:32 AM
11/20/12 11:32 AM
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Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
jamesc
master
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master
Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
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Quote:
Quote:
personally i think the HV pump sucking the pan dry is a wives tale.
I will send you my burnt rod.....Was running 9.5 quarts, and starved one rod.
everyone is entitled to their opinion mine is that if you have 2 1/2 gallons of oil in an engine and can't keep things wet there's something else wrong other than the size of the pump, the oil pumps job is pretty simple. if you have that much oil in suspension then the return is inadequate, clearances too loose or some other oil control problem is going on (or a combination).
if you burned something up the HV pump was NOT the cause
what people just don't seem to grasp is that no matter WHAT size pump is on an engine if at any given point in the operating conditions the oil pressure is the same then the flow of oil through the engine is the same...period
if you're at 7000 rpm and have 75# of pressure with a stock pump and 75# with a HV pump then the flow THROUGH the engine is the same.
IF you have 75# with a stock pump and 60# with a HV pump (due to relief spring differences) then the STOCK pump is circulating more oil through the engine.
don't believe me ask a hydraulics engineer
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Re: High Volume vs Standard Volume Oil Pump
[Re: jamesc]
#1337697
11/20/12 11:52 AM
11/20/12 11:52 AM
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Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
Streetwize
master
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master
Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
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JamesC,
Well yes and no, Gauge pressure doesn't always tell the entire story since there are both series and parallel hydraulic circuits in the motor and the gauge pressure reading locations in the circuit can vary somewhat by the motor. It depends to some degree where the failure is. For example if a #5 rod bearing fails it severely reduces the oil to the rods downstream on the crank from it, but the rods upstream and closer to the pump (though much lower) could still have adequate pressure. Depending on where the sender is on that motor you may see different gauge readings. for example a small block sender is pretty close to the pump as it's off the #5 main while on a big block the sender is off the back of the block (clear on the other side of the crank) while the pump is up front. so Low pressure at idle to me is a bit relative, In line with what Rickster finds on his motor, small blocks always seem to have way better GAUGE idle pressure than big blocks from my experience, I think the location of the sender relative to the pump discharge has a bit to do with it but I may be wrong.
As I said earlier one of the best ways to insure circuit flow is to tackle the pump discharge efficiency since it potentially has a positive effect on everything in the system.
I agree a 9.5 quart system sucking dry and leading to a rod failure seems unusual, a motor autospy can usually determine the cause and effect.
Last edited by Streetwize; 11/20/12 12:16 PM.
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Re: High Volume vs Standard Volume Oil Pump
[Re: Streetwize]
#1337698
11/20/12 01:00 PM
11/20/12 01:00 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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With our limited experience,the standard non hi-volume pump will not keep up with the demands of a hemi above 6500rpm.We have seen increased bearing wear as well as topend wear.If the pump starves any area and oil passages, cavitation can occurr,air lubes nothing.As we have mentioned time and time again a hemi on a adverage 10 second pass will circulate 10 qurts of oil aprox. 3xs.This is why the need for larger sumps and more elaborate oil systems are critical.Volume is as important or more so as pressure.We have seen the big SS race hemis with hardly any oil pressure at idle and aprox.65# down track survive because of the volume of oil in the sump,accumulaters and a big pump to deliver that volume.That a hemi retains more oil in the top makes a dual line system and large sump critical over 7000rpm. My opinion only. If the results don't support the theory,find another theory. 
Last edited by B G Racing; 11/20/12 05:36 PM.
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